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View Full Version : why aren't there 'autoflaps'?


iffy IFE
27th Feb 2001, 14:20
In this world of autopilots, autothrottles, autobrakes, autoland and so on, why hasn't anyone developed autoflaps?

In some aircraft (744, for e.g.), I believe the FMC already calculates flap retraction and extension speeds and displays them on the PFD during takeoff/climb and approach respectively. So why hasn't the next step been taken to actually automate the process?

I believe the 777 has overspeed protection for the flaps, retracting them until the IAS drops enough to allow them to resume their selected position, but that's not quite what I mean.

As an interested PAX & PPL wannabe, can someone tell me why this idea wouldn't work or wouldn't be a good thing?

Cheers

iffy IFE

DeltaTango
27th Feb 2001, 14:57
Flaps is something to be used with caution...

alot of drag if you don't notice the indicator you will get quite alarmed if they should suddenly deploy.

Why isn't there a radio altimeter connected to the gear so controllers would'nt have to ask if you are "all greens?"

ex:
plane spec.:
speed at flare - 120.
max speed w flaps full(landing config) - 128.
stall flaps full - 105
stall flaps 50% - 123.
Now imagine a slightly seedy approachand perhaps a bad flare and the speed does/t drop, it even reaches 130 for a few seconds....

this is where you find out if you can actually shake worse than a stick shaker.....

twistedenginestarter
27th Feb 2001, 18:19
iffy

Good idea. Perhaps nobody thought of it before you.

My personal guess is that they only make computers do the things that they alone can do like operate the brakes, land the plane etc.

Putting the flaps and wheels down is something that can be trusted to the human pilot so it's cheaper to leave him to do it.

Also automate too many things and questions will start to be asked why we're paying this person such a huge amount of money just to tell the passengers that's Mont Blanc on the left hand side and its x degrees Celsius in Gerona, not that they can hear anyway.

iffy IFE
27th Feb 2001, 19:12
Delta Tango: thx for the reply. I understand the issue now.

twistedenginestarter: not trying to promote it as a good idea (and certainly not as mine). Just interested in finding out why, when aircraft manufacturers have tried to automate many things, they haven't had a go at this. And now, thanks to Delta Tango, I know. Decided to make this the thing I'd learn today...